An essential guardian of the neuronal genome is the transcriptional repressor REST/NRSF. The long-term goal is to better understand the transcriptional and epigenetic circuitry important for neuronal cell fate, in both physiological and pathological contexts. The objective of this grant proposal is to generate a genome-wide view of REST/NRSF target genes by performing ChIP-Seq and RNA-seq in adult neural stem cells. The central hypothesis is REST/NRSF is essential for stem cell quiescence and is a master negative regulator of adult hippocampal neurogenesis. The rationale for the proposed research is that understanding developmental mechanisms controlling the neuronal lineage program have the potential to further therapeutic approaches to an increasing number of mental disorders linked to neuronal loss or aberrant neuronal function. Thus, the proposed study is relevant to that part of NIH's mission that relates to gaining fundamental knowledge that will potentially help treat neurological disorders. Guided by strong preliminary data, this hypothesis will be tested by pursuing two specific aims: 1) Genome-wide identification of REST/NRSF targets in adult NSC chromatin and 2) Transcriptome analysis of adult NSCs during quiescence, proliferation, and neuronal differentiation. Aim 1 will focus on performing ChIP-Seq of REST/NRSF in adult hippocampal neural stem cells. Aim 2 will focus on performing RNA-seq from adult NSCs under conditions of quiescence, proliferation, and neuronal differentiation. Aim 2 will also identify which targets are dependent on REST/NRSF by comparing ChIP-Seq targets to gene expression analysis from REST/NRSF conditional knockout mice generated in our laboratory. The conceptual framework and approach is innovative, because it is the first study to apply state-of-the-art deep sequencing techniques to a physiologically relevant adult neural stem cell system in order to identify a genome-wide view of REST/NRSF target genes. The proposed R21 grant is significant, because it is expected to advance and expand our basic understanding of transcriptional networks regulating stem cell quiescence, proliferation, and neuronal differentiation which may be of particular importance for restoring cognitive function after brain damage or disease. PUBLIC HEALTH RELEVANCE: Disease, degeneration or traumatic injury of the nervous system are among the greatest public health concerns in the United States and are generally considered irreparable, often causing catastrophic damage to the functional capacity of the individual. Now, however, characterization of neural stem cells residing within specific germinal centers of the brain and in cell culture raises hope that functional regeneration of nervous tissue may be feasible, if we learn to exploit adult neurogenesis for clinical benefit. The research proposal will lead to improved understanding of neural stem cell biology, possibly leading to the development of new drugs for repair and regeneration of the nervous system.